Recliner mechanisms have been used to releasably secure a seat back against a seat base in a motor vehicle. The seat back is typically adjustable for comfort by the recliner mechanism over a normal range of travel with respect to the seat base, and the seat base is rigidly affixed to a floor of the motor vehicle. Such a recliner mechanism can comprise a toothed pawl mounted to the seat base which engages a toothed sector assembly attached to the seat back. A comfort adjust mechanism moves the pawl out of engagement with the sector, permitting the sector (and therefore the seat back) to pivot.
An easy entry latch permits the seat back to be dumped, that is, rotated to a full forward end of the normal range of travel. The term easy entry, as used here, refers to the ability of a seat back to be pivoted so as to allow access behind the seat back, typically to a second row of seats or a rear compartment of a motor vehicle. U.S. Pat. No. 5,414,897 discloses a single component latch assembly that can be used as an easy entry latch for a vehicle seat, comprising a latch that engages a latch plate. The term single component refers to the fact that the latch is the component which engages the latch plate and the release handle is attached directly to the latch. Such designs can have problems with release efforts. That is, in some circumstances, high release efforts are required to rotate the latch out of engagement with the latching plate. It would be desirable to provide an easy entry latch mechanism for a vehicle seat where the seat back stays in position with respect to the seat base when subjected to rapid accelerations and decelerations as can be experienced in a motor vehicle, while maintaining reasonable release efforts to rotate the release handle.
In view of the foregoing, it is an object of the present invention to provide an easy entry latch mechanism which can resist unlatching in response to sudden acceleration or deceleration. It is an additional object of the present invention to provide an easy entry latch mechanism having relatively low release efforts. It is another related object of the present invention to provide such a latch mechanism that is insensitive to vibration and is highly reliable in operation.